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1.
Mol Immunol ; 147: 1-9, 2022 Jul.
Article in English | MEDLINE | ID: covidwho-1859982

ABSTRACT

The novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been shown to hijack angiotensin converting enzyme 2 (ACE2) for entry into mammalian cells. A short isoform of ACE2, termed deltaACE2 (dACE2), has recently been identified. In contrast to ACE2, the short dACE2 isoform lacks the ability to bind the spike protein of SARS-CoV-2. Several studies have proposed that expression of ACE2 and/or dACE2 is induced by interferons (IFNs). Here, we report that drug-targeted inhibition or silencing of Unc51-like kinase 1 (ULK1) results in repression of type I IFN-induced expression of the dACE2 isoform. Notably, dACE2 is expressed in various squamous tumors. In efforts to identify pharmacological agents that target this pathway, we found that fisetin, a natural flavonoid, is an ULK1 inhibitor that decreases type I IFN-induced dACE2 expression. Taken together, our results establish a requirement for ULK1 in the regulation of type I IFN-induced transcription of dACE2 and raise the possibility of clinical translational applications of fisetin as a novel ULK1 inhibitor.


Subject(s)
Angiotensin-Converting Enzyme 2 , COVID-19 , Animals , Interferon-alpha , Mammals , Protein Isoforms/genetics , Protein Isoforms/metabolism , SARS-CoV-2
2.
Int J Mol Sci ; 23(7)2022 Mar 28.
Article in English | MEDLINE | ID: covidwho-1834807

ABSTRACT

Angiotensin-converting enzyme 2 (ACE2) is a protein widely expressed in numerous cell types, with different biological roles mainly related to the renin-angiotensin system. Recently, ACE2 has been in the spotlight due to its involvement in the SARS-CoV-2 entry into cells. There are no data available regarding the expression of ACE2 and its short-ACE2 isoform at the protein level on human spermatozoa. Here, protein expression was demonstrated by western blot and the percentage of sperm displaying surface ACE2 was assessed by flow cytometry. Immunocytochemistry assays showed that full-length ACE2 was mainly expressed in sperm midpiece, while short ACE2 was preferentially distributed on the equatorial and post-acrosomal region of the sperm head. To our knowledge, this is the first study demonstrating the expression of protein ACE2 on spermatozoa. Further studies are warranted to determine the role of ACE2 isoforms in male reproduction.


Subject(s)
Angiotensin-Converting Enzyme 2 , COVID-19 , Humans , Male , Protein Isoforms/genetics , Protein Isoforms/metabolism , SARS-CoV-2 , Spermatozoa/metabolism
3.
Sci Rep ; 12(1): 2145, 2022 02 09.
Article in English | MEDLINE | ID: covidwho-1692555

ABSTRACT

The most common host entry point of human adapted coronaviruses (CoV) including SARS-CoV-2 is through the initial colonization in the nostril and mouth region which is responsible for spread of the infection. Most recent studies suggest that the commercially available oral and nasal rinse products are effective in inhibiting the viral replication. However, the anti-viral mechanism of the active ingredients present in the oral rinses have not been studied. In the present study, we have assessed in vitro enzymatic inhibitory activity of active ingredients in the oral mouth rinse products: aloin A and B, chlorhexidine, eucalyptol, hexetidine, menthol, triclosan, methyl salicylate, sodium fluoride and povidone, against two important proteases of SARS-CoV-2 PLpro and 3CLpro. Our results indicate only aloin A and B effectively inhibited proteolytic activity of PLpro with an IC50 of 13.16 and 16.08 µM. Interestingly, neither of the aloin isoforms inhibited 3CLpro enzymatic activity. Computational structural modelling of aloin A and B interaction with PLpro revealed that, both aloin isoforms form hydrogen bond with Tyr268 of PLpro, which is critical for their proteolytic activity. Furthermore, 100 ns molecular dynamics (MD) simulation studies predicted that both aloin isoforms have strong interaction with Glu167, which is required for PLpro deubiquitination activity. Our results from the in vitro deubiquitinase inhibition assay show that aloin A and B isomers exhibit deubiquitination inhibitory activity with an IC50 value of 15.68 and 17.51 µM, respectively. In conclusion, the isoforms of aloin inhibit both proteolytic and the deubiquitinating activity of SARS-CoV-2 PLpro, suggesting potential in inhibiting the replication of SARS-CoV-2 virus.


Subject(s)
Coronavirus Papain-Like Proteases/metabolism , Emodin/analogs & derivatives , SARS-CoV-2/enzymology , Animals , Binding Sites , COVID-19/pathology , COVID-19/virology , Cell Survival/drug effects , Chlorocebus aethiops , Coronavirus 3C Proteases/antagonists & inhibitors , Coronavirus 3C Proteases/metabolism , Coronavirus Papain-Like Proteases/antagonists & inhibitors , Emodin/chemistry , Emodin/metabolism , Emodin/pharmacology , Humans , Molecular Dynamics Simulation , Protein Isoforms/chemistry , Protein Isoforms/metabolism , Protein Isoforms/pharmacology , SARS-CoV-2/isolation & purification , Vero Cells
4.
Molecules ; 27(3)2022 Jan 29.
Article in English | MEDLINE | ID: covidwho-1667252

ABSTRACT

Aspirin (also known as acetylsalicylic acid) is a drug intended to treat fever, pain, or inflammation. Treatment of moderate to severe cases of COVID-19 using aspirin along with dexamethasone has gained major attention globally in recent times. Thus, the purpose of this study was to use High-Performance Liquid Chromatography (HPLC) to evaluate the in vitro inhibition of CYP3A2 enzyme activity using aspirin in rat liver microsomes (RLMs). In this study, an efficient and sensitive HPLC method was developed using a reversed phase C18 column (X Bridge 4.6 mm × 150 mm, 3.5 µm) at 243 nm using acetonitrile and water (70:30 v/v). The linearity (r2 > 0.999), precision (<15%), accuracy and recovery (80-120%), limit of detection (5.60 µM and 0.06 µM), limit of quantification (16.98 µM and 0.19 µM), and stability of the newly developed method were validated for dexamethasone and 6ß-hydroxydexamethasone, respectively, following International Conference on Harmonization (ICH) guidelines. This method was applied in vitro to measure CYP3A2 activity. The results showed that aspirin competitively inhibits 6ß-hydroxylation (CYP3A2 activity) with an inhibition constant (Ki) = 95.46 µM and the concentration of the inhibitor causing 50% inhibition of original enzyme activity (IC50) = 190.92 µM. This indicated that there is a minimal risk of toxicity when dexamethasone and aspirin are co-administrated and a very low risk of toxicity and drug interaction with drugs that are a substrate for CYP3A2 in healthcare settings.


Subject(s)
Aspirin/pharmacology , Chromatography, High Pressure Liquid/methods , Cytochrome P-450 CYP3A/metabolism , Animals , Aspirin/chemistry , COVID-19/drug therapy , Cytochrome P-450 CYP3A/drug effects , Cytochrome P-450 Enzyme Inhibitors/metabolism , Cytochrome P-450 Enzyme System/metabolism , Dexamethasone/analogs & derivatives , Dexamethasone/pharmacology , Male , Microsomes, Liver/metabolism , Pharmaceutical Preparations/metabolism , Protein Isoforms/metabolism , Rats , Rats, Sprague-Dawley , Reproducibility of Results , SARS-CoV-2/drug effects , SARS-CoV-2/pathogenicity
5.
Epigenomics ; 14(3): 153-162, 2022 02.
Article in English | MEDLINE | ID: covidwho-1622527

ABSTRACT

Smoking could predispose individuals to a more severe COVID-19 by upregulating a particular gene known as mdig, which is mediated through a number of well-known histone modifications. Smoking might regulate the transcription-activating H3K4me3 mark, along with the transcription-repressing H3K9me3 and H3K27me3 marks, in a way to favor SARS-CoV-2 entry by enhancing the expression of ACE2, NRP1 and NRP2, AT1R, CTSD and CTSL, PGE2 receptors 2-4, SLC6A20 and IL-6, all of which interact either directly or indirectly with important receptors, facilitating viral entry in COVID-19.


Lay abstract The role of smoking in development of several respiratory diseases has been clearly established. A significant proportion of these deleterious effects is mediated through epigenetic mechanisms, particularly histone modifications. Recent evidence indicates that smoking induces the expression of a mediator known as mdig, which in turn alters the transcription of several key proteins that have been implicated in development of COVID-19.


Subject(s)
COVID-19/genetics , Dioxygenases/genetics , Epigenesis, Genetic , Histone Demethylases/genetics , Histones/genetics , Nuclear Proteins/genetics , Protein Processing, Post-Translational , Smoking/genetics , Angiotensin-Converting Enzyme 2/genetics , Angiotensin-Converting Enzyme 2/metabolism , COVID-19/diagnosis , COVID-19/metabolism , COVID-19/virology , Cathepsin D/genetics , Cathepsin D/metabolism , Cathepsin L/genetics , Cathepsin L/metabolism , Dioxygenases/metabolism , Histone Demethylases/metabolism , Histones/metabolism , Humans , Interleukin-6/genetics , Interleukin-6/metabolism , Membrane Transport Proteins/genetics , Membrane Transport Proteins/metabolism , Methylation , Neuropilin-1/genetics , Neuropilin-1/metabolism , Neuropilin-2/genetics , Neuropilin-2/metabolism , Nuclear Proteins/metabolism , Protein Isoforms/genetics , Protein Isoforms/metabolism , Receptor, Angiotensin, Type 1/genetics , Receptor, Angiotensin, Type 1/metabolism , Receptors, Prostaglandin E/genetics , Receptors, Prostaglandin E/metabolism , Risk Factors , SARS-CoV-2/genetics , SARS-CoV-2/growth & development , SARS-CoV-2/metabolism , Smoking/metabolism , Smoking/pathology , Virus Internalization
6.
Sci Rep ; 11(1): 24336, 2021 12 21.
Article in English | MEDLINE | ID: covidwho-1585788

ABSTRACT

ACE2 is a membrane protein that regulates the cardiovascular system. Additionally, ACE2 acts as a receptor for host cell infection by human coronaviruses, including SARS-CoV-2 that emerged as the cause of the on-going COVID-19 pandemic and has brought unprecedented burden to economy and health. ACE2 binds the spike protein of SARS-CoV-2 with high affinity and shows little variation in amino acid sequence meaning natural resistance is rare. The discovery of a novel short ACE2 isoform (deltaACE2) provides evidence for inter-individual differences in SARS-CoV-2 susceptibility and severity, and likelihood of developing subsequent 'Long COVID'. Critically, deltaACE2 loses SARS-CoV-2 spike protein binding sites in the extracellular domain, and is predicted to confer reduced susceptibility to viral infection. We aimed to assess the differential expression of full-length ACE2 versus deltaACE2 in a panel of human tissues (kidney, heart, lung, and liver) that are implicated in COVID-19, and confirm ACE2 protein in these tissues. Using dual antibody staining, we show that deltaACE2 localises, and is enriched, in lung airway epithelia and bile duct epithelia in the liver. Finally, we also confirm that a fluorescently tagged SARS-CoV-2 spike protein monomer shows low binding at lung and bile duct epithelia where dACE2 is enriched.


Subject(s)
Angiotensin-Converting Enzyme 2/metabolism , SARS-CoV-2/physiology , Spike Glycoprotein, Coronavirus/metabolism , Angiotensin-Converting Enzyme 2/chemistry , Angiotensin-Converting Enzyme 2/genetics , Bile Ducts/metabolism , Bile Ducts/virology , Binding Sites , COVID-19/pathology , COVID-19/virology , Humans , Lung/metabolism , Lung/virology , Microscopy, Fluorescence, Multiphoton , Protein Binding , Protein Isoforms/chemistry , Protein Isoforms/genetics , Protein Isoforms/metabolism , Receptors, Virus/chemistry , Receptors, Virus/metabolism , SARS-CoV-2/isolation & purification , Spike Glycoprotein, Coronavirus/chemistry , Virus Internalization
7.
EBioMedicine ; 73: 103672, 2021 Nov.
Article in English | MEDLINE | ID: covidwho-1568646

ABSTRACT

BACKGROUND: Phospho-Akt1 (pAkt1) undergoes prolyl hydroxylation at Pro125 and Pro313 by the prolyl hydroxylase-2 (PHD2) in a reaction decarboxylating α-ketoglutarate (αKG). We investigated whether the αKG supplementation could inhibit Akt-mediated activation of platelets and monocytes, in vitro as well as in vivo, by augmenting PHD2 activity. METHODS: We treated platelets or monocytes isolated from healthy individuals with αKG in presence of agonists in vitro and assessed the signalling molecules including pAkt1. We supplemented mice with dietary αKG and estimated the functional responses of platelets and monocytes ex vivo. Further, we investigated the impact of dietary αKG on inflammation and thrombosis in lungs of mice either treated with thrombosis-inducing agent carrageenan or infected with SARS-CoV-2. FINDINGS: Octyl αKG supplementation to platelets promoted PHD2 activity through elevated intracellular αKG to succinate ratio, and reduced aggregation in vitro by suppressing pAkt1(Thr308). Augmented PHD2 activity was confirmed by increased hydroxylated-proline and enhanced binding of PHD2 to pAkt in αKG-treated platelets. Contrastingly, inhibitors of PHD2 significantly increased pAkt1 in platelets. Octyl-αKG followed similar mechanism in monocytes to inhibit cytokine secretion in vitro. Our data also describe a suppressed pAkt1 and reduced activation of platelets and leukocytes ex vivo from mice supplemented with dietary αKG, unaccompanied by alteration in their number. Dietary αKG significantly reduced clot formation and leukocyte accumulation in various organs including lungs of mice treated with thrombosis-inducing agent carrageenan. Importantly, in SARS-CoV-2 infected hamsters, we observed a significant rescue effect of dietary αKG on inflamed lungs with significantly reduced leukocyte accumulation, clot formation and viral load alongside down-modulation of pAkt in the lung of the infected animals. INTERPRETATION: Our study suggests that dietary αKG supplementation prevents Akt-driven maladies such as thrombosis and inflammation and rescues pathology of COVID19-infected lungs. FUNDING: Study was funded by the Department of Biotechnology (DBT), Govt. of India (grants: BT/PR22881 and BT/PR22985); and the Science and Engineering Research Board, Govt. of India (CRG/000092).


Subject(s)
Ketoglutaric Acids/therapeutic use , Prolyl Hydroxylases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Thrombosis/prevention & control , Animals , Blood Platelets/cytology , Blood Platelets/drug effects , Blood Platelets/metabolism , COVID-19/pathology , COVID-19/prevention & control , COVID-19/veterinary , COVID-19/virology , Cricetinae , Dietary Supplements , Down-Regulation/drug effects , Humans , Ketoglutaric Acids/pharmacology , Lung/metabolism , Lung/pathology , Mesocricetus , Mice , Mice, Inbred BALB C , Monocytes/cytology , Monocytes/drug effects , Monocytes/metabolism , Phosphorylation , Platelet Aggregation/drug effects , Protein Isoforms/genetics , Protein Isoforms/metabolism , Proto-Oncogene Proteins c-akt/genetics , SARS-CoV-2/isolation & purification , SARS-CoV-2/physiology , Thrombosis/chemically induced , Thrombosis/pathology , Thrombosis/veterinary
8.
Biol Pharm Bull ; 44(11): 1617-1634, 2021.
Article in English | MEDLINE | ID: covidwho-1551286

ABSTRACT

The CYP3A subfamily, which includes isoforms CYP3A4, CYP3A5, and CYP3A7 in humans, plays important roles in the metabolism of various endogenous and exogenous substances. Gene and protein expression of CYP3A4, CYP3A5, and CYP3A7 show large inter-individual differences, which are caused by many endogenous and exogenous factors. Inter-individual differences can cause negative outcomes, such as adverse drug events and disease development. Therefore, it is important to understand the variations in CYP3A expression caused by endo- and exogenous factors, as well as the variation in the metabolism and kinetics of endo- and exogenous substrates. In this review, we summarize the factors regulating CYP3A expression, such as bile acids, hormones, microRNA, inflammatory cytokines, drugs, environmental chemicals, and dietary factors. In addition, variations in CYP3A expression under pathological conditions, such as coronavirus disease 2019 and liver diseases, are described as examples of the physiological effects of endogenous factors. We also summarize endogenous and exogenous substrates metabolized by CYP3A isoforms, such as cholesterol, bile acids, hormones, arachidonic acid, vitamin D, and drugs. The relationship between the changes in the kinetics of these substrates and the toxicological effects in our bodies are discussed. The usefulness of these substrates and metabolites as endogenous biomarkers for CYP3A activity is also discussed. Notably, we focused on discrimination between CYP3A4, CYP3A5, and CYP3A7 to understand inter-individual differences in CYP3A expression and function.


Subject(s)
Cytochrome P-450 CYP3A/metabolism , Animals , COVID-19/metabolism , Gene Expression Regulation/drug effects , Gene Expression Regulation/physiology , Humans , Liver Diseases/metabolism , Protein Isoforms/metabolism
9.
Int J Biol Sci ; 17(14): 3954-3967, 2021.
Article in English | MEDLINE | ID: covidwho-1449161

ABSTRACT

Furin is a proprotein convertase that activates different kinds of regulatory proteins, including SARS-CoV-2 spike protein which contains an additional furin-specific cleavage site. It is essential in predicting cancer patients' susceptibility to SARS-CoV-2 and the disease outcomes due to varying furin expressions in tumor tissues. In this study, we analyzed furin's expression, methylation, mutation rate, functional enrichment, survival rate and COVID-19 outcomes in normal and cancer tissues using online databases, and our IHC. As a result, furin presented with biased expression profiles in normal tissues, showing 12.25-fold higher than ACE2 in the lungs. The furin expression in tumors were significantly increased in ESCA and TGCT, and decreased in DLBC and THYM, indicating furin may play critical mechanistic functions in COVID-19 viral entry into cells in these cancer patients. Line with furin over/downexpression, furin promoter hypo-/hyper-methylation may be the regulatory cause of disease and lead to pathogenesis of ESCA and THYM. Furthermore, presence of FURIN-201 isoform with functional domains (P_proprotein, Peptidase_S8 and S8_pro-domain) is highest in all cancer types in comparison to other isoforms, demonstrating its use in tumorigenesis and SARS-Cov-2 entry into tumor tissues. Furin mutation frequency was highest in UCES, and its mutation might elevate ACE2 expression in LUAD and UCEC, reduce ACE2 expression in COAD, elevate HSPA5 expression in PAAD, and elevate TMPRSS2 expression in BRCA. These results showed that furin mutations mostly increased expression of ACE2, HSPA5, and TMPRSS2 in certain cancers, indicating furin mutations might facilitate COVID-19 cell entry in cancer patients. In addition, high expression of furin was significantly inversely correlated with long overall survival (OS) in LGG and correlated with long OS in COAD and KIRC, indicating that it could be used as a favorable prognostic marker for cancer patients' survival. GO and KEGG demonstrated that furin was mostly enriched in genes for metabolic and biosynthetic processes, retinal dehydrogenase activity, tRNA methyltransferase activity, and genes involving COVID-19, further supporting its role in COVID-19 and cancer metabolism. Moreover, Cordycepin (CD) inhibited furin expression in a dosage dependent manner. Altogether, furin's high expression might not only implies increased susceptibility to SARS-CoV-2 and higher severity of COVID-19 symptoms in cancer patients, but also it highlights the need for cancer treatment and therapy during the COVID-19 pandemic. CD might have a potential to develop an anti-SARS-CoV-2 drug through inhibiting furin expression.


Subject(s)
Antineoplastic Agents/therapeutic use , COVID-19/virology , Deoxyadenosines/therapeutic use , Furin/metabolism , Neoplasms/metabolism , Antineoplastic Agents/pharmacology , COVID-19/complications , Cell Line, Tumor , Deoxyadenosines/pharmacology , Disease Susceptibility , Furin/antagonists & inhibitors , Furin/genetics , Humans , Neoplasms/complications , Protein Isoforms/metabolism , Serine Endopeptidases/metabolism
10.
Int J Mol Sci ; 22(17)2021 Aug 29.
Article in English | MEDLINE | ID: covidwho-1374429

ABSTRACT

Heat shock proteins (HSPs) are a large group of chaperones found in most eukaryotes and bacteria. They are responsible for the correct protein folding, protection of the cell against stressors, presenting immune and inflammatory cytokines; furthermore, they are important factors in regulating cell differentiation, survival and death. Although the biological function of HSPs is to maintain cell homeostasis, some of them can be used by viruses both to fold their proteins and increase the chances of survival in unfavorable host conditions. Folding viral proteins as well as replicating many different viruses are carried out by, among others, proteins from the HSP70 and HSP90 families. In some cases, the HSP70 family proteins directly interact with viral polymerase to enhance viral replication or they can facilitate the formation of a viral replication complex and/or maintain the stability of complex proteins. It is known that HSP90 is important for the expression of viral genes at both the transcriptional and the translational levels. Both of these HSPs can form a complex with HSP90 and, consequently, facilitate the entry of the virus into the cell. Current studies have shown the biological significance of HSPs in the course of infection SARS-CoV-2. A comprehensive understanding of chaperone use during viral infection will provide new insight into viral replication mechanisms and therapeutic potential. The aim of this study is to describe the molecular basis of HSP70 and HSP90 participation in some viral infections and the potential use of these proteins in antiviral therapy.


Subject(s)
HSP70 Heat-Shock Proteins/metabolism , HSP90 Heat-Shock Proteins/metabolism , Virus Diseases/pathology , COVID-19/metabolism , COVID-19/pathology , COVID-19/virology , DNA Viruses/physiology , Humans , Protein Isoforms/metabolism , RNA Viruses/physiology , SARS-CoV-2/isolation & purification , Virus Diseases/metabolism , Virus Diseases/virology
11.
Virus Res ; 304: 198545, 2021 10 15.
Article in English | MEDLINE | ID: covidwho-1351860

ABSTRACT

The influenza A virus genome contains 8 gene segments encoding 10 commonly recognized proteins. Additional protein products have been identified, including PB1-F2 and PA-X. We report the in-silico identification of novel isoforms of PB1-F2 and PA-X in influenza virus genomes sequenced from avian samples. The isoform observed in PA-X includes a mutated stop codon that should extend the protein product by 8 amino acids. The isoform observed in PB1-F2 includes two nonsense mutations that should truncate the N-terminal region of the protein product and remove the entire mitochondrial targeting domain. Both isoforms were uncovered during automatic annotation of CEIRS sequence data. Nominally termed PA-X8 and PB1-F2-Cterm, both predicted isoforms were subsequently found in other annotated influenza genomes previously deposited in GenBank. Both isoforms were noticed due to discrepant annotations output by two annotation engines, indicating a benefit of incorporating multiple algorithms during gene annotation.


Subject(s)
Influenza A virus , Influenza, Human , Base Sequence , Humans , Influenza A virus/genetics , Influenza A virus/metabolism , Protein Isoforms/genetics , Protein Isoforms/metabolism , Viral Proteins/metabolism
12.
World J Microbiol Biotechnol ; 36(11): 164, 2020 Sep 30.
Article in English | MEDLINE | ID: covidwho-1343003

ABSTRACT

Laccases (EC 1.10.3.2) are multi-copper oxidases that can degrade several xenobiotics, including textile dyes. Present study investigated the nature of laccase isoforms induced by 2,6-dimethylaniline in Cyathus bulleri cultivated on basal salt medium. Two isoforms, LacI and LacII were identified and purified by a combination of ultrafiltration and ion-exchange chromatography. The MS spectrum of the two proteins displayed a number of non-identical and identical molecular peaks (m/z), and, the latter were mapped to protein originating from the previously reported Laccase (Lcc) 1 gene. The LacI isoform exhibited higher catalytic efficiency (Kcat/Km) towards 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid), 2,6-dimethoxyphenol, guaiacol and pyrogallol and was tolerant to high levels of chloride ions and resistant to EDTA. Higher decolorization of several dyes such as Direct Scarlet B (67%), Reactive Brilliant blue-R (96%), Direct Orange 34 (50%) and Reactive Red198 (95%) by the LacI isoform makes it a good candidate for degradation of synthetic dyes. The decolorization of Direct Orange 34 by laccases is being reported for the first time. Many of the properties exhibited by this isoform make it a good candidate for large scale production and applications for use in the dyeing industry.


Subject(s)
Coloring Agents/metabolism , Cyathus/metabolism , Laccase/metabolism , Textiles , Amino Acid Sequence , Aniline Compounds/metabolism , Culture Media/chemistry , Hydrogen-Ion Concentration , Oxidoreductases/metabolism , Protein Isoforms/metabolism , Substrate Specificity , Sulfonic Acids/metabolism
13.
PLoS One ; 16(6): e0253458, 2021.
Article in English | MEDLINE | ID: covidwho-1286869

ABSTRACT

L-Dopa decarboxylase (DDC) is the most significantly co-expressed gene with ACE2, which encodes for the SARS-CoV-2 receptor angiotensin-converting enzyme 2 and the interferon-inducible truncated isoform dACE2. Our group previously showed the importance of DDC in viral infections. We hereby aimed to investigate DDC expression in COVID-19 patients and cultured SARS-CoV-2-infected cells, also in association with ACE2 and dACE2. We concurrently evaluated the expression of the viral infection- and interferon-stimulated gene ISG56 and the immune-modulatory, hypoxia-regulated gene EPO. Viral load and mRNA levels of DDC, ACE2, dACE2, ISG56 and EPO were quantified by RT-qPCR in nasopharyngeal swab samples from COVID-19 patients, showing no or mild symptoms, and from non-infected individuals. Samples from influenza-infected patients were analyzed in comparison. SARS-CoV-2-mediated effects in host gene expression were validated in cultured virus-permissive epithelial cells. We found substantially higher gene expression of DDC in COVID-19 patients (7.6-fold; p = 1.2e-13) but not in influenza-infected ones, compared to non-infected subjects. dACE2 was more elevated (2.9-fold; p = 1.02e-16) than ACE2 (1.7-fold; p = 0.0005) in SARS-CoV-2-infected individuals. ISG56 (2.5-fold; p = 3.01e-6) and EPO (2.6-fold; p = 2.1e-13) were also increased. Detected differences were not attributed to enrichment of specific cell populations in nasopharyngeal tissue. While SARS-CoV-2 virus load was positively associated with ACE2 expression (r≥0.8, p<0.001), it negatively correlated with DDC, dACE2 (r≤-0.7, p<0.001) and EPO (r≤-0.5, p<0.05). Moreover, a statistically significant correlation between DDC and dACE2 expression was observed in nasopharyngeal swab and whole blood samples of both COVID-19 and non-infected individuals (r≥0.7). In VeroE6 cells, SARS-CoV-2 negatively affected DDC, ACE2, dACE2 and EPO mRNA levels, and induced cell death, while ISG56 was enhanced at early hours post-infection. Thus, the regulation of DDC, dACE2 and EPO expression in the SARS-CoV-2-infected nasopharyngeal tissue is possibly related with an orchestrated antiviral response of the infected host as the virus suppresses these genes to favor its propagation.


Subject(s)
Angiotensin-Converting Enzyme 2/metabolism , COVID-19/pathology , Dopa Decarboxylase/metabolism , Adaptor Proteins, Signal Transducing/genetics , Adaptor Proteins, Signal Transducing/metabolism , Adult , Aged , Angiotensin-Converting Enzyme 2/genetics , Area Under Curve , Aromatic-L-Amino-Acid Decarboxylases , COVID-19/virology , Dopa Decarboxylase/genetics , Down-Regulation , Epithelial Cells/cytology , Epithelial Cells/metabolism , Erythropoietin/genetics , Erythropoietin/metabolism , Female , Humans , Male , Middle Aged , Nasopharynx/metabolism , Protein Isoforms/genetics , Protein Isoforms/metabolism , RNA-Binding Proteins/genetics , RNA-Binding Proteins/metabolism , ROC Curve , SARS-CoV-2/genetics , SARS-CoV-2/isolation & purification , Up-Regulation , Viral Load
14.
Int J Mol Sci ; 22(12)2021 Jun 09.
Article in English | MEDLINE | ID: covidwho-1264471

ABSTRACT

Interstitial lung diseases (ILDs) comprise different fibrotic lung disorders characterized by cellular proliferation, interstitial inflammation, and fibrosis. The JAK/STAT molecular pathway is activated under the interaction of a broad number of profibrotic/pro-inflammatory cytokines, such as IL-6, IL-11, and IL-13, among others, which are increased in different ILDs. Similarly, several growth factors over-expressed in ILDs, such as platelet-derived growth factor (PDGF), transforming growth factor ß1 (TGF-ß1), and fibroblast growth factor (FGF) activate JAK/STAT by canonical or non-canonical pathways, which indicates a predominant role of JAK/STAT in ILDs. Between the different JAK/STAT isoforms, it appears that JAK2/STAT3 are predominant, initiating cellular changes observed in ILDs. This review analyzes the expression and distribution of different JAK/STAT isoforms in ILDs lung tissue and different cell types related to ILDs, such as lung fibroblasts and alveolar epithelial type II cells and analyzes JAK/STAT activation. The effect of JAK/STAT phosphorylation on cellular fibrotic processes, such as proliferation, senescence, autophagy, endoplasmic reticulum stress, or epithelial/fibroblast to mesenchymal transition will be described. The small molecules directed to inhibit JAK/STAT activation were assayed in vitro and in in vivo models of pulmonary fibrosis, and different JAK inhibitors are currently approved for myeloproliferative disorders. Recent evidence indicates that JAK inhibitors or monoclonal antibodies directed to block IL-6 are used as compassionate use to attenuate the excessive inflammation and lung fibrosis related to SARS-CoV-2 virus. These altogether indicate that JAK/STAT pathway is an attractive target to be proven in future clinical trials of lung fibrotic disorders.


Subject(s)
Janus Kinases/metabolism , Lung Diseases, Interstitial/pathology , STAT Transcription Factors/metabolism , Cellular Senescence , Endoplasmic Reticulum Stress , Humans , Interleukins/metabolism , Janus Kinases/antagonists & inhibitors , Janus Kinases/genetics , Lung Diseases, Interstitial/drug therapy , Lung Diseases, Interstitial/metabolism , Protein Isoforms/genetics , Protein Isoforms/metabolism , Protein Kinase Inhibitors/chemistry , Protein Kinase Inhibitors/metabolism , Protein Kinase Inhibitors/therapeutic use , STAT Transcription Factors/antagonists & inhibitors , STAT Transcription Factors/genetics , Signal Transduction
15.
J Mol Biol ; 433(8): 166875, 2021 04 16.
Article in English | MEDLINE | ID: covidwho-1108437

ABSTRACT

The coronavirus nucleocapsid protein (N) controls viral genome packaging and contains numerous phosphorylation sites located within unstructured regions. Binding of phosphorylated SARS-CoV N to the host 14-3-3 protein in the cytoplasm was reported to regulate nucleocytoplasmic N shuttling. All seven isoforms of the human 14-3-3 are abundantly present in tissues vulnerable to SARS-CoV-2, where N can constitute up to ~1% of expressed proteins during infection. Although the association between 14-3-3 and SARS-CoV-2 N proteins can represent one of the key host-pathogen interactions, its molecular mechanism and the specific critical phosphosites are unknown. Here, we show that phosphorylated SARS-CoV-2 N protein (pN) dimers, reconstituted via bacterial co-expression with protein kinase A, directly associate, in a phosphorylation-dependent manner, with the dimeric 14-3-3 protein, but not with its monomeric mutant. We demonstrate that pN is recognized by all seven human 14-3-3 isoforms with various efficiencies and deduce the apparent KD to selected isoforms, showing that these are in a low micromolar range. Serial truncations pinpointed a critical phosphorylation site to Ser197, which is conserved among related zoonotic coronaviruses and located within the functionally important, SR-rich region of N. The relatively tight 14-3-3/pN association could regulate nucleocytoplasmic shuttling and other functions of N via occlusion of the SR-rich region, and could also hijack cellular pathways by 14-3-3 sequestration. As such, the assembly may represent a valuable target for therapeutic intervention.


Subject(s)
14-3-3 Proteins/chemistry , 14-3-3 Proteins/metabolism , Coronavirus Nucleocapsid Proteins/chemistry , Coronavirus Nucleocapsid Proteins/metabolism , Amino Acid Sequence , Binding Sites/genetics , Coronavirus Nucleocapsid Proteins/genetics , Cyclic AMP-Dependent Protein Kinases/genetics , Cyclic AMP-Dependent Protein Kinases/metabolism , Escherichia coli , Humans , Mutation , Phosphopeptides/chemistry , Phosphopeptides/metabolism , Phosphoproteins/chemistry , Phosphoproteins/genetics , Phosphoproteins/metabolism , Phosphorylation , Phosphoserine/metabolism , Protein Binding , Protein Isoforms/chemistry , Protein Isoforms/metabolism , RNA, Viral/metabolism , Substrate Specificity
16.
Cell Stem Cell ; 28(2): 331-342.e5, 2021 02 04.
Article in English | MEDLINE | ID: covidwho-1009887

ABSTRACT

ApoE4, a strong genetic risk factor for Alzheimer disease, has been associated with increased risk for severe COVID-19. However, it is unclear whether ApoE4 alters COVID-19 susceptibility or severity, and the role of direct viral infection in brain cells remains obscure. We tested the neurotropism of SARS-CoV2 in human-induced pluripotent stem cell (hiPSC) models and observed low-grade infection of neurons and astrocytes that is boosted in neuron-astrocyte co-cultures and organoids. We then generated isogenic ApoE3/3 and ApoE4/4 hiPSCs and found an increased rate of SARS-CoV-2 infection in ApoE4/4 neurons and astrocytes. ApoE4 astrocytes exhibited enlarged size and elevated nuclear fragmentation upon SARS-CoV-2 infection. Finally, we show that remdesivir treatment inhibits SARS-CoV2 infection of hiPSC neurons and astrocytes. These findings suggest that ApoE4 may play a causal role in COVID-19 severity. Understanding how risk factors impact COVID-19 susceptibility and severity will help us understand the potential long-term effects in different patient populations.


Subject(s)
Apolipoproteins E/metabolism , Brain/pathology , Brain/virology , COVID-19/virology , Induced Pluripotent Stem Cells/virology , SARS-CoV-2/physiology , Tropism/physiology , Adenosine Monophosphate/analogs & derivatives , Adenosine Monophosphate/pharmacology , Alanine/analogs & derivatives , Alanine/pharmacology , Animals , Antiviral Agents/pharmacology , Astrocytes/drug effects , Astrocytes/pathology , Astrocytes/virology , Cell Differentiation , Chlorocebus aethiops , Humans , Nerve Degeneration/pathology , Neurites/pathology , Neurons/drug effects , Neurons/pathology , Neurons/virology , Organoids/drug effects , Organoids/pathology , Organoids/virology , Protein Isoforms/metabolism , Synapses/pathology , Vero Cells
17.
J Cell Mol Med ; 24(21): 12864-12868, 2020 11.
Article in English | MEDLINE | ID: covidwho-780917

ABSTRACT

The SARS-coronavirus 2 is the aetiologic agent COVID-19. ACE2 has been identified as a cell entry receptor for the virus. Therefore, trying to understand how the gene is controlled has become a major goal. We silenced the expression of STAT3α and STAT3ß, and found that while silencing STAT3α causes an increase in ACE2 expression, silencing STAT3ß causes the opposite effect. Studying the role of STAT3 in ACE2 expression will shed light on the molecular events that contribute to the progression of the disease and that the different roles of STAT3α and STAT3ß in that context must be taken in consideration. Our results place STAT3 in line with additional potential therapeutic targets for treating COVID-19 patients.


Subject(s)
Angiotensin-Converting Enzyme 2/metabolism , STAT3 Transcription Factor/metabolism , Angiotensin-Converting Enzyme 2/genetics , Binding Sites , COVID-19 , Humans , MCF-7 Cells , Promoter Regions, Genetic , Protein Isoforms/genetics , Protein Isoforms/metabolism , SARS-CoV-2/drug effects , STAT3 Transcription Factor/genetics
18.
Nat Struct Mol Biol ; 27(8): 763-767, 2020 08.
Article in English | MEDLINE | ID: covidwho-640223

ABSTRACT

SARS-CoV-2 is thought to have emerged from bats, possibly via a secondary host. Here, we investigate the relationship of spike (S) glycoprotein from SARS-CoV-2 with the S protein of a closely related bat virus, RaTG13. We determined cryo-EM structures for RaTG13 S and for both furin-cleaved and uncleaved SARS-CoV-2 S; we compared these with recently reported structures for uncleaved SARS-CoV-2 S. We also biochemically characterized their relative stabilities and affinities for the SARS-CoV-2 receptor ACE2. Although the overall structures of human and bat virus S proteins are similar, there are key differences in their properties, including a more stable precleavage form of human S and about 1,000-fold tighter binding of SARS-CoV-2 to human receptor. These observations suggest that cleavage at the furin-cleavage site decreases the overall stability of SARS-CoV-2 S and facilitates the adoption of the open conformation that is required for S to bind to the ACE2 receptor.


Subject(s)
Betacoronavirus/genetics , Host-Pathogen Interactions/genetics , Peptidyl-Dipeptidase A/chemistry , Receptors, Virus/chemistry , Spike Glycoprotein, Coronavirus/chemistry , Angiotensin-Converting Enzyme 2 , Animals , Betacoronavirus/metabolism , Betacoronavirus/ultrastructure , Binding Sites , COVID-19 , Chiroptera/virology , Coronavirus Infections/virology , Cryoelectron Microscopy , Evolution, Molecular , Furin/chemistry , Gene Expression , HEK293 Cells , Humans , Models, Molecular , Pandemics , Peptidyl-Dipeptidase A/genetics , Peptidyl-Dipeptidase A/metabolism , Pneumonia, Viral/virology , Protein Binding , Protein Conformation, alpha-Helical , Protein Conformation, beta-Strand , Protein Interaction Domains and Motifs , Protein Isoforms/chemistry , Protein Isoforms/genetics , Protein Isoforms/metabolism , Protein Stability , Proteolysis , Receptors, Virus/genetics , Receptors, Virus/metabolism , Recombinant Proteins/chemistry , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , SARS-CoV-2 , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/metabolism , Structural Homology, Protein
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